statsmodels.robust.norms.RamsayE.psi¶
- RamsayE.psi(z)[source]¶
The psi function for Ramsay’s Ea estimator
The analytic derivative of rho
- Parameters:¶
- zarray_like
1d array
- Returns:¶
- psi
ndarray
psi(z) = z*exp(-a*|z|)
- psi
Last update:
Dec 23, 2024